Check draft



fr' aga July-16, 1929. A, c, wn'm;l 1.720.869

CHECK DRAFT Filed April 29, 1927 yAnnul' 0 INVENTOR.

ATT RNEYS.

'Patented July 16, 1929.

'ALVIN C. WITTIG', OF KIVIIINKVAUKHE,y WISCONSIN.

CHECK DRAFT.

Application filed April 29,

This invention relates toimprovements in check drafts, and more particularly to'floating check drafts for furnaces and heaters.

It is one of theobjects of the present invention to provide a floating check draft for mounting in a-furnace or heater smoke pipe which is automat-ic in operation.

A further object of the invention is 4to provide a check draft of the class described which is automatically operated by the draft through the pipe thereby constantly regulating the check on the fire to correspond with the draft and changes in the draft, resulting in a saving in fuel and a uniform fire.

A further object of the invention is to provide a check draft which will not require any attention nor adjustments.

A further object 0f the invention is to pro-` vide a check draft of the class described which may be releasably locked in closed position if it is desired to bring up the fire very quickly. V

A further object of the invention is to pro* vide a check draft of the class described which is of very simple construction and with which the smoke pipe of any heater may be very easily equipped.

A further object of the invention is to provide a floating check ldraft which is inexpensive to manufacture and install, is strong and durable, and is well adapted for the purpose set forth.

l/Vith the above and other objects in view the invention consists of the improved iioating check draft and its parts and combinations as set forth in the claim, and all equivalents thereof.

In the accompanying drawing in which the same reference characters indicate the same parts in both of the views Fig. 1 is a vertical sectional view showing the improved floating check draft; and

Fig. 2 is a plan view of the same.

Referring now more particularly to the drawing it will appear that the numeral 5 indicates a cylindrical member which is hollow and has a bottom portion 6 and a top 7 provided with a circular opening 8 of a substantial size. The wall of said member 5 is provided with a pair of openings k9 from which extend opposed pipes 10, each of which are connected with pipe sect-ions 11. The member 5 is adapted to be interposed in the smoke pipe of a furnace or heater and one 1927. Serial No. 187,522.

of the pipe sections 11 connected thereto will extend to the chimney and the other pipe section 11 will extend to the furnace.

A bracket or supporting member 12 is sccured to the top 7 ofthe member 5 and spans the opening 8. A rod 13 is threaded through the intermediate portion of the bracket and the lower portion of the rod is formed with an eyelet 13 to which is secured one end portion ofan elongated Icoiled spring 14. The other end portion of the spring is attached to the cent-er of a valve plate 15. Said plate 15 is positioned within the cylindrical member 5 below the opening 8 in the top thereof and is of a diameter greater than the diameter of the opening 8. The plate is thin and very light, being preferably formed of aluminum. The rod-13 may be adjusted with respect to the bracket and is held in adjusted position by means of a nut 16.

The undersurface of the top 7 of the member 5 is covered by a sheet 17 of insulating material as asbestos, said sheet, of course having a circular opening` therein corresponding to Y the opening in the top 7.

In use, the cylindrical member is positioned in the smoke pipe of ka furnace or heater as described and the draft through the pipe will cause a suction which will draw down the plate 15 away from the opening 8, allowing air to enter through the opening thus exposed t0 act as a checl. The downward movement of the plate will be against the tension of the spring 14 which should be adjusted so as to normally hold the plate tightly against the' insulating sheet 17 and of course if there is no draft through the pipe the plate will remain in closed position and the amount which the plate will draw away from the opening depends entirely on the strength of the draft. Hence, if there is a strong draft the opening will be greatly exposed to give a strong counter-acting check, whereas if the draft is weak the opening rwill be only slightly exposed and in this manner the needed draft on the fire is automatically regulated. It has been found in practice that the plate will con stantly bob up and down slightly because of the fluctuations in the draft. The sheet 17 serves not only as an insulating medium but deadens the sound and prevents a metallic ring caused by contactbetween the plate and the top.

It is sometimes desirable that the plate be held in closed position to prevent a check as for instance when a lire is being built or a quick re is desired. For that purpose a rod 18 is pivotally mounted through a side portion ol the wall o'lthe member 5 in proximity to the top thereof and the rod is held against withdrawal by Cotter pins 19. If the outer end portion of the rod is pulled downwardly, as shown in dotted lines in Fig. 1 the inner end portion ot' the rod will be raised and will engage the mid-portion of the plate 15 to hold the same firmly in closed position. The outer end portion of the rod 18 has depending therefrom a chain i2() which has at its lower end portion a hoolr 21 which may be engaged with the lower rim portion of the member 5 to releasably hold the rod in plate engaging position.

From the Yforegoing description it will be seen that the improved floating cheek draft is of very simple and novel construction, and is well adapted for the purpose described.

That I claim as my invention is:

The combination with a heater smoke pipe, of a hollow member interposed therein, said hollow member having an opening therein, a bracket attached to said hollow member and spanning the opening, an adjustable normally contracted spring member suspended from the mid portion of said bracket, a thin plate centrally attached to said spring member and positioned within the hollow member to normally lcontrol the opening therein, a pivotal r'od locking member extending adjacent said plate for releasably holding the same in a closing position with respect to the opening, and means for locking said rod in a plate engaging position.

In testimony whereof, I aflix my signature.

ALVIN C. VITTIG. 

